Anti-collapsible umbrella

ABSTRACT

This invention improves umbrellas for anti-collapsible use in gusty winds, where the umbrella main cover will have holes therein arranged outwardly around the umbrella shaft part way out to the main cover periphery, and a secondary cover will overlie the main cover and all holes therein. Elastic ties are connected between the periphery of the secondary cover and the umbrella arms at their outer ends, normally stretching the secondary cover radially tight and at least peripherally against the main cover. However, the elastic ties allow separation of the main and secondary covers. Thus, under high or gusty wind conditions, air accumulated under the main cover can be vented upwardly through the main cover holes to between the covers and radially then to beyond the secondary cover periphery, relieving the mechanical forces tending to invert and collapse the umbrella. Nonetheless, the secondary cover will yet overlies said holes to block rain from passing through the holes and wetting the user.

BACKGROUND OF THE INVENTION

[0001] Umbrellas most commonly have a structural frame including an elongated shaft, and arms extended radially off of and transversely away from one end of the shaft for stretching out a flexible fabric cover that defines a broad barrier or canopy extended symmetrically and radially away from the shaft. The arms can be manipulated from an opened position with the barrier extended transverse to the shaft to a closed position with the arms in general parallel alignment with the shaft, effective for reducing the barrier size to almost nothing and making the umbrella more compact for nonuse storage or handling.

[0002] When using an umbrella, the user can grip the handle end of the shaft and hold the barrier in an elevated position so that rain drops will be diverted transversely thereby and not hit the user's body close to the shaft. In windy conditions where the rain falls along varying nonvertical angles, the user commonly will point the shaft into the wind and lower the barrier so as to yet block the driving rain from reaching the user. This also helps keep the wind from collecting under the flexible barrier.

[0003] Of importance to this invention, it is common that winds can create excessive forces on the umbrella arms and held flexible cover to invert or back fold the arms and cover past their opened position and away from the shaft handle. Once the umbrella has been inverted, it might be sufficiently ripped or bent to be unsightly, poorly functional and/or even useless.

[0004] As the public demands affordable, lightweight and compact umbrellas, and due possibly to the public's believed infrequent need for using umbrellas generally and/or during extreme windy conditions, costly or reinforced umbrella suited to withstand extreme windy conditions without collapsing generally are not accepted. Consequently, inverted umbrellas live on.

SUMMARY OF THE INVENTION

[0005] An object of the invention is to provide a modified umbrella design, not involving reinforcing the umbrella frame, operable to withstand use in high or gusty windy conditions that otherwise could invert the umbrella and render its unusable.

[0006] A further object of the invention is to provide an umbrella usable in high wind conditions, where the improved features lie in the cover structures and not in a reinforced or otherwise modified frame structure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007]FIG. 1 is a side view of an umbrella incorporating the subject invention, as one might see it from under the main umbrella cover with the near side of the frame and the remote side of the cover being in elevation, shown opened and in substantially windless condition;

[0008]FIG. 2 is an side elevational view similar to FIG. 1, except showing the umbrella in a typical dynamic position when subjected to windy conditions;

[0009]FIG. 3 is a top plan view of the umbrella of FIG. 1, partly broken away for clarity of disclosure, showing the top and secondary covers and supporting arms as planar developments and ignoring the retreating curvature of these components as they are further from the center shaft.

DETAILED DESCRIPTION OF THE INVENTION

[0010] As the invention can be incorporated in any conventional umbrella, a typical umbrella 10 will first be described.

[0011] The illustrated umbrella 10 is comprised of a frame 12 having an elongated shaft 14 with a handle 16 near its lower end and with a plurality of arms 18 pivoted near their inner ends 20 relative to the shaft near its upper end; and a flexible cover 24 is centrally connected to the shaft 14 proximate the inner ends 20 of the arms 18 and connected at radial locations along the respective underlying arms and at peripheral end locations 26 to the respective underlying arms.

[0012] The cover 24 typically is contoured and sized to be stretched substantially tight or wrinkle free in the opened condition of the umbrella 10, whereupon it is extended radially from and transversely to the shaft 14 for creating a large area barrier or canopy 28 disposed symmetrically of the shaft.

[0013] The frame 12 can be of any conventional style, to allow the arms 18 and cover 24 to be folded to a compact condition (not shown) that eliminates or minimizes the size of the end barrier 28. For example, a slide 32 can be mounted to move along the shaft 14, and thrust links 34 can be pivoted near their inner ends 36 to the slide and near their outer ends 38 to the arms 18.

[0014] The umbrella 10 can be opened by moving the slide 32 to be close to the upper end of the shaft 14 (as illustrated), causing the thrust links 34 to pivot the arms 18 until they extend radially transverse to the shaft and the main cover 24 is stretched out tightly by the raised arms. The umbrella 10 can be closed upon moving the slide 32 toward the shaft handle 16, which shifts the thrust links 34 and arms 18 into generally parallel side-by-side association with the shaft 14. This reduces the circumferential tension of the fabric cover 24 and allows it to be folded around and/or lie loosely along the shaft 14. A strap (not shown) typically secured at one end to the cover 24 can be wound around and over the folded arms and cover to hold the umbrella closed.

[0015] Radially near the shaft, the stretched cover 24 typically will be curved somewhat as a segment of a sphere disposed generally symmetrically around the shaft, having a generally concave underside 40 and a generally convex outer or upper side 42; and the arms 18, particularly radially near the shaft, are correspondingly bowed, but yet lie in different respective planes each extended axially through the shaft.

[0016] Gusting winds readily collect against the cover underside 40, applying upward forces on the opened umbrella arms 18 and cover 24 that can exceed the strength of the arms and cover to invert or collapse the umbrella to where one or more of the arms 18 and cover 24 might be back folded beyond the normal open position. In a typical collapsed or back folded position, the outer or upper side 42 might be curved concavely and/or one or more of the arms 18 could be aligned in the direction toward the umbrella handle 16 but with its outer end 26 more remote from the handle than its inner end 20. Once any of the arms 18, thrust links 34, etc. might be inverted or back folded, the umbrella can be extensively damaged and even unusable.

[0017] To minimize the effects of wind on the umbrella 10, the present invention provides a secondary cover 44 to overlie the central part of the main cover 24, and a plurality of holes 46 are provided in the main cover at locations underlying the secondary cover 44. The secondary cover 44 would have its center secured relative to the shaft 14 as at 50, and elastic ties 52 would be connected between the secondary cover periphery 54 and the outer ends 26 of the arms 18. The connection 50 of the secondary cover 44 to the shaft 14 preferably will be axially spaced above the connection 20 of the main cover 24 to the shaft.

[0018] With the umbrella 10 opened, the elastic ties 52 normally will hold the secondary cover 44 radially stretched out during windless or low wind conditions, and the covers 24, 44 at the secondary cover periphery 54 will be overlapping and touching. The secondary cover 44 radially inward of its contact with the curved main cover 24 will continue spaced above the main cover somewhat conically toward the shaft 14, defining an enclosure 56 directly overlying and exposed to some radially inward main cover holes 46 i. The secondary cover 44 would be contoured the same as the main cover 24 or possibly of a slightly larger radius or degree of curvature.

[0019] The elastic ties 52 when stretched will allow the covers 24, 44 at the secondary cover periphery 54 to be separated, while yet overlying the main cover holes 46.

[0020] Thus, under gusty wind conditions, air trapped against the underside surface 40 of the main cover 24 can escape upwardly through the main cover holes 46 (as arrows A-1) into the enclosure 56 between the covers 24, 44, and the elastically extended ties 52 allow axial separation of the covers 24, 44 at the secondary cover periphery 54 to form outlet passages 58 radially from the enclosure, allowing the air therein to escape past the secondary cover periphery (as arrows A-2). The secondary cover 44 can be ballooned upwardly in a dynamic manner, evenly or unevenly where one side might be higher than the other or while one side might even remain in contact with the main cover.

[0021] The energy of the winds is thus dissipated or released upwardly through the main cover holes 46 and radially from between the main and secondary covers, reducing the mechanical forces tending the invert the umbrella.

[0022] Further, the elastic ties 52 will return the covers 24, 44 to the touching conditions at the secondary cover periphery 54 when the wind gust subsides, again having the secondary cover 44 yet overlie the main cover holes 46 to block rain from passing through the holes.

[0023] In a preferred design, the secondary cover periphery 54 might lie approximately between 50-75% of the radial distance from the shaft to the main cover periphery 26, and might be spaced radially beyond the outermost ring of holes 460 by possibly between 1-4 inches. The holes 46 can be of varied sizes, between ½-3 inches across, and at random positions or arrays radially and circumferentially spaced around the shaft 14, but the total area of the holes preferably might be equal to between 20-45% of the main cover area radially inwardly of where the holes are in the main cover.

[0024] The main cover 24 and the secondary cover 44 might of the same flexible material, and they might have the same colors and/or patterns.

[0025] While only a single embodiment of the invention has been disclosed, it is apparent that minor variations might be made without varying from the inventive concept. Accordingly, the invention is to be limited not by the disclosure but by the scope of the following claims. 

What is claimed as my invention is:
 1. An umbrella suited for anti-collapsible use in gusty winds, comprising the combination of a frame having an elongated shaft, a plurality of arms pivoted near their inner ends relative to the shaft near one of its ends and extended radially of said shaft, a main flexible cover overlying the arms and connected centrally to the shaft and along the radial arms to near its periphery proximate the outer arm ends, operable with said umbrella in the opened condition to have said arms angled transversely of the shaft and said cover stretched somewhat as a sphere segment symmetrically disposed around the shaft and having a generally convex outer upper side facing in the direction remotely away from the other shaft end; the main cover having holes therein arranged in a central array spaced outwardly around the shaft no further from the shaft than between 50-75% of the radial distance from the shaft to the main cover periphery; and a secondary cover overlying the main cover and all holes therein and connected centrally to the shaft, the secondary cover periphery having circumferentially spaced portions overlying respectively underlying arms, and elastic cords connected between said portions and the respective arms at their outer ends, whereby the opened umbrella under generally windless conditions or between gusts of high winds will have said cords stretch said secondary cover substantially tight radially of the shaft and outwardly beyond the holes and further and under gusty wind conditions will have said cords elastically extended to allow the main and secondary covers to separate at the secondary cover periphery to form radial passages for accommodating air flow upwardly through the main cover holes to between the covers and radially then to beyond the secondary cover periphery while said secondary cover yet overlies said holes to block rain from passing through the holes.
 2. An anti-collapsible umbrella according to claim 1, further comprising the combination of the connection of the secondary cover to the shaft being axially spaced above the connection of the main cover to the shaft, operable for defining an air filled enclosure directly overlying said holes for accommoating immediate air passage therefrom under gusty wind conditions.
 3. An anti-collapsible umbrella according to claim 1, further comprising the combination of the main and secondary covers having similar contours in the area where the covers lie adjacent one another.
 4. An anti-collapsible umbrella according to claim 1, further comprising the combination the secondary cover periphery being spaced radially outward beyond the outermost holes in the main cover by between 1-4 inches.
 5. An anti-collapsible umbrella according to claim 1, further comprising the combination the main and secondary covers being of the same flexible material, color and pattern. 